Self-referencing hierarchy in GridView

Question

Hi,

I recently read that self-referencing hierarchy is now supported by Telerik's radGridView. Unfortunately, I have been unable to locate any demos, tutorials, or sample code to look at. Is this information available?

Here is my current code that I'm working with:

private void SetupElementsGrid(){
radGvElements.Columns.Clear();
radGvElements.MasterGridViewTemplate.Columns.Add(new GridViewTextBoxColumn("ElementID"));
radGvElements.MasterGridViewTemplate.Columns.Add(new GridViewTextBoxColumn("ProtocolTemplateID"));
radGvElements.MasterGridViewTemplate.Columns.Add(new GridViewTextBoxColumn("ParentElementID"));
radGvElements.MasterGridViewTemplate.Columns.Add(new GridViewTextBoxColumn("ElementNumber"));
radGvElements.MasterGridViewTemplate.Columns.Add(new GridViewTextBoxColumn("ElementDesc"));

radGvElements.Columns["ElementID"].IsVisible = false;
radGvElements.Columns["ProtocolTemplateID"].IsVisible = false;
radGvElements.Columns["ParentElementID"].IsVisible = false;

radGvElements.Columns["ElementNumber"].HeaderText = "Element Number";
radGvElements.Columns["ElementDesc"].HeaderText = "Element Description";

radGvElements.MasterGridViewTemplate.AutoSizeColumnsMode = GridViewAutoSizeColumnsMode.Fill;

GridViewTemplate childTemplate = new GridViewTemplate();   
childTemplate.Columns.Add(new GridViewTextBoxColumn("ElementID"));
childTemplate.Columns.Add(new GridViewTextBoxColumn("ProtocolTemplateID"));
childTemplate.Columns.Add(new GridViewTextBoxColumn("ParentElementID"));
childTemplate.Columns.Add(new GridViewTextBoxColumn("ElementNumber"));
childTemplate.Columns.Add(new GridViewTextBoxColumn("ElementDesc"));

//childTemplate.Columns["ElementID"].IsVisible = false;
//childTemplate.Columns["ProtocolTemplateID"].IsVisible = false;
//childTemplate.Columns["ParentElementID"].IsVisible = false;

//childTemplate.Columns["ElementNumber"].HeaderText = "Element Number";
//childTemplate.Columns["ElementDesc"].HeaderText = "Element Description";

childTemplate.AutoSizeColumnsMode = GridViewAutoSizeColumnsMode.Fill;

if(radGvElements.MasterGridViewTemplate.ChildGridViewTemplates.Count == 0)
{                   
    radGvElements.MasterGridViewTemplate.ChildGridViewTemplates.Add(childTemplate);
}

GridViewRelation relation = new GridViewRelation(radGvElements.MasterGridViewTemplate);
relation.ChildTemplate = childTemplate;
relation.RelationName = "ParentChild";
relation.ParentColumnNames.Add("ElementID");
relation.ChildColumnNames.Add("ParentElementID");
radGvElements.Relations.Add(relation);

ProtocolTemplate = (ProtocolTemplate)ProtocolTemplatesBindingSource.CurrencyManager.List[ProtocolTemplatesBindingSource.CurrencyManager.Position];
ElementsBindingSource.DataSource = ProtocolTemplate.Elements;
radGvElements.DataSource = ElementsBindingSource;

radGvElements.DataSource = ElementsBindingSource;
childTemplate.DataSource = ElementsBindingSource;

}

Sample data would look like this:

ElementID -- ProtocolTemplateID -- ParentElementID -- ElementNumber -- ElementDesc 1 -- 1 -- 1 -- 1.0 -- ParentLevel1 2 -- 1 -- 1 -- 1.1 -- ChildLevel1 3 -- 1 -- 1 -- 1.2 -- ChildLevel2 4 -- 1 -- 4 -- 2.0 -- ParentLevel2

With my current code, this displays as:

Row 1 -- Row1 -- Row2 -- Row3 Row 2 Row 3 Row 4 -- Row 4

It should be:

Row 1 -- Row 2 -- Row 3 Row 4

Also, another problem is with the portion of code I have commented out. This code causes a NullReferenceException error to be thrown and I don't know why.

If anyone could help me out with the above code, or even point me in the direction of some reading material, I would be very grateful.

Answer 1

Self-referencing hierarchies are supported in the RadGrid for ASP.NET AJAX. That may be what you heard. I haven't heard of the same feature in the WinForms RadGridView.

Answer 2

Got it figured out. All is well.